Embodiments of the present invention generally relate to entry security, and particularly to key assemblies and lock assemblies having elements capable of biasing locking pins and mechanical and design characteristics that substantially increase the number of key/lock combinations, thereby inhibiting the unauthorized replication of the key assembly.
Locks are often intended to provide the security of permitting only authorized ingress and/or egress for a given entry. The existence of a locked entry and/or the inability to unlock a locked entry may indicate that unauthorized passage through the entry is prohibited and/or to deter such unauthorized passage. Locking such entries may therefore control when, who, and/or what passes through the entry.
Various attempts may be made to gain unauthorized passage through a locked entry. For example, an individual lacking authorization may attempt to gain entry by breaking the door and/or breaking the lock. However, these actions suffer from many drawbacks, including, for example, the noise associated with breaking the door and/or lock, the resulting visual or audible indication that unauthorized ingress/egress may being occurring or has occurred, the potential need for tools to carry out the act of breaking the door and/or lock, and the time and energy associated with such a break.
Another option for unauthorized entry that may not involve some of the challenges associated with physically breaking the lock or door is duplicating the key that unlocks the lock, or use other devices in an attempt to manipulate, or pick, the lock so as to unlock the lock. Duplicating keys for many types of locks merely requires duplicating the general physical shape of the blade of the key, recreating the profile of key bits and the shape and depth of holes or cavities in the key. Such unauthorized duplication may be achieved by filing, cutting, and/or machining a blank of material, such as a key blank or other blank that is or can be machined or manipulated to suitably match the shape and configuration of the key.
Locks to an entry must, in addition to allowing authorized individuals to enter, have specific key profiles that prevent unauthorized key duplication, either by an unauthorized entrant or an unauthorized professional assembling the duplicate key. Additionally, a variety of top-secret institutions require keys with more combinations that are difficult to duplicate in order to avoid unauthorized entry.
Present day flat blade keys often have depressions of different depths in the key blade or, in the cases of high-security entry, have holes that are of different shapes. Additionally, there are keys having a variety of shapes, such as round cross-sectioned keys; and keys having outward projecting bits; all for the purpose of preventing unauthorized entry and/or unauthorized key duplication.
Thus, a need exists for key assemblies configured to prevent or deter successful unauthorized duplication of the key assembly. Further, a need exists to provide a key assembly that has mechanical properties and design requirements that increase the possible key/lock combinations that would inhibit unauthorized successful duplication of the key assembly, and thereby provide increased security against unauthorized ingress or egress through an entry.